SOS tip for acute back pain / lumbago
Has "shot the witch" and you do not even know how to lie back pain, the following can make the worst pain more bearable: you make a sturdy box, e.g. put a moving box in bed / couch, blanket over it, and stored on it the lower legs. It is important that the cardboard is high enough to have a 90 degree angle.
There are in medical supply houses or now just at a discounter special square cushions for this purpose, which are not cheap and cheap to stow.
The cardboard can be unfolded to save space and set up in use.